fix: avoid blocking canvas refs on local url checks

lib/canvas/generate-image.ts

@@ -52,6 +52,22 @@ const SUPPORTED_CANVAS_PROVIDER_TYPES = new Set([
   "krea",
 ]);
 
+function summarizeReferenceImageHosts(urls: string[]) {
+  return Array.from(
+    new Set(
+      urls
+        .map((value) => {
+          try {
+            return new URL(value).host;
+          } catch {
+            return "";
+          }
+        })
+        .filter(Boolean)
+    )
+  );
+}
+
 function parseImagesFromMarkdown(markdown: string): ParsedImage[] {
   const imageRegex = /!\[([^\]]*)\]\(([^)]+)\)/g;
   const matches = [...markdown.matchAll(imageRegex)];
@@ -202,14 +218,23 @@ export async function generateCanvasImage(
   ).slice(0, 12);
   const { kept: reachableReferenceImages, dropped: unreachableReferenceImages } =
     await filterReachableRemoteUrls(normalizedReferenceImages, { timeoutMs: 3000 });
+  const effectiveReferenceImages = normalizedReferenceImages;
   if (unreachableReferenceImages.length > 0) {
-    console.warn("[Canvas Generate Image] Dropping unreachable reference images:", {
+    console.warn("[Canvas Generate Image] Local reachability check failed for some reference images:", {
       count: unreachableReferenceImages.length,
       urls: unreachableReferenceImages.slice(0, 6),
+      hosts: summarizeReferenceImageHosts(unreachableReferenceImages),
     });
   }
   if (normalizedReferenceImages.length > 0 && reachableReferenceImages.length === 0) {
-    throw new Error("参考图片链接不可访问，请重新上传后再试");
+    console.warn(
+      "[Canvas Generate Image] All reference images failed local reachability check; proceeding with original URLs.",
+      {
+        count: normalizedReferenceImages.length,
+        hosts: summarizeReferenceImageHosts(normalizedReferenceImages),
+        debugLabel,
+      }
+    );
   }
 
   console.info("[Canvas Generate Image] Started:", {
@@ -220,6 +245,8 @@ export async function generateCanvasImage(
     imageCount,
     requestedReferenceImageCount: normalizedReferenceImages.length,
     reachableReferenceImageCount: reachableReferenceImages.length,
+    effectiveReferenceImageCount: effectiveReferenceImages.length,
+    referenceImageHosts: summarizeReferenceImageHosts(effectiveReferenceImages),
     selectedModelRef: selectedModel.model.id,
     selectedModelId: selectedModel.model.modelId,
     providerType: provider.type,
@@ -230,10 +257,10 @@ export async function generateCanvasImage(
     {
       role: "user" as const,
       content:
-        reachableReferenceImages.length > 0
+        effectiveReferenceImages.length > 0
           ? [
               { type: "text" as const, text: prompt },
-              ...reachableReferenceImages.map((url) => ({
+              ...effectiveReferenceImages.map((url) => ({
                 type: "image_url" as const,
                 image_url: { url },
               })),